Combined machine for punching and laser cutting of flat sheet metal

ABSTRACT

A combined machine is described, for punching and laser cutting of a flat sheet metal. The machine comprises a fixed base ( 1 ), a fixed punching head ( 7 ), a laser cutting head ( 10 ) and a manipulator ( 4 ) for the movement of the sheet metal ( 6 ) on a Cartesian plane (XY). The laser cutting head ( 10 ) is carried by a variable-aperture compass structure ( 9 ), which is mobile along a linear guide ( 8 ).

The present invention relates to a combined machine for punching and laser cutting of flat sheet metal.

Combined machines for punching and laser cutting of flat sheet metals are long-time known solutions which add—to the undoubted efficiency of individual punching and laser cutting machines—the operating flexibility of the combination of the two processes, that is a single manipulation of the sheet metal with the laser cutting replacing punching tools of complex shape. Thereby, each of the two processes, punching and laser cutting, may be best used on the sheet metal itself to be processed according to the design geometry of the piece and of the available punches.

More general architecture for an individual punching machine is the one of a fixed punching press, equipped with a tool changing device, with the sheet to be processed mobile on a Cartesian plane (XY). Contrarily, the most widespread architecture for the individual laser machine is the one with the sheet to be processed fixed and the head mobile, although solutions with fixed laser head and mobile sheet, or hybrid solutions, exist.

Combined punching and laser cutting machines are any punching machines which accommodate a laser head and not vice versa. The result is that the combined machines are at least provided with a fixed punching head, with a laser cutting head, also fixed, and with a Cartesian manipulator for the movement of the sheet metal on the plane (XY). A machine of this type is represented and described for example in EP-0491747-B1.

Furthermore, combined machines are known which are equipped with a mobile laser cutting head which allows adding the advantage of the low inertia of the motion of the laser head with respect to the inertia of the movement of the sheet. Solutions exist for the mobility of the laser head on a single axis (y) or on two orthogonal axes (xy). Obviously, the mobility of the laser heads in a single direction (y) or in the two directions (xy) makes controlling the combined motion of the laser head and of the Cartesian manipulator (XY) of the sheet metal, complex.

Combined machines with mobile laser cutting head in a single direction (y) are described in JP-2006088214-A, JP-2007038286-A and JP-2009018334-A. The first patent shows a laser cutting head with single-directional mobility (y) in direction parallel to the one of the manipulator (Y) of the sheet metal. The second patent modifies the mobility (y) of the laser head and the design of the manipulator (XY) so as to allow the transversal through cutting of a sheet metal without interfering with the manipulator itself and its grippers. Lastly, the third patent enhances the two previous ones by adding a mechanical solution which compensates for the thermal expansion of the control screw of the movement of the laser head.

A combined machine is also known with mobility (xy) of the laser head in addition to the mobility (XY) of the manipulator of the sheet metal.

In view of this state of the art, the object of the present invention is to make a combined machine with fixed punching head and mobile laser cutting head which has a different and more convenient type of mobility of the laser head.

In accordance with the invention, such an object is achieved with a combined machine for punching and laser cutting of a flat sheet metal, comprising a fixed base, a fixed punching head, a mobile laser cutting head and a manipulator for the movement of the sheet metal in a Cartesian plane (XY), characterized in that said laser cutting head is carried by a compass structure equipped with fixed-radius (ρ) polar mobility (θ) and with a linear mobility (y).

According to a preferred embodiment, the polar-linear mobility is ensured by two independent actuators which determine the translation of the compass structure along a linear guide and the opening and closure of the compass structure itself.

The movements of the laser head may be obtained by means of rotating motors or linear motors or with screw motorizations.

The combination of the Cartesian movements of the manipulator (XY) for the mobility of the sheet metal and of the low-inertia polar-linear movements of the laser cutting head allow absolutely competitive performances and work quality to be obtained.

Possible embodiments of a combined machine according to the present invention are shown by way of non-limiting example in the accompanying drawings, in which:

FIG. 1 shows a combined machine with rotating motors in condition of extended compass positioned in a generic point of the linear guide;

FIG. 2 shows the same machine in condition of compact compass positioned in a generic point of the linear guide;

FIG. 3 shows a combined machine with linear motors in condition of compact compass positioned in a generic point of the linear guide;

FIG. 4 shows a combined machine with screw motorization in condition of compact compass positioned in a generic point of the linear guide;

FIG. 5 shows a further variant of the combined machine according to the present invention;

FIG. 6 shows the construction detail of an example of compass structure for supporting and moving the laser cutting head of the combined machine according to the present invention;

FIG. 7 shows that a combined machine according to the present invention, in particular the one in FIGS. 1 and 2, is capable of performing a complete through cut of the sheet metal without the movement of the manipulator and the mobility of the laser head interfering with each other.

The combined machine in FIGS. 1 and 2 comprises a fixed base 1 which has a bottom section 2 and a top section 3. In the example shown, the base is substantially C-shaped but may also be O-shaped as a closed portal.

Manipulator 4 is inserted between the two sections 2 and 3 which by means of grippers 5, supports a flat sheet metal 6 thus ensuring the controlled movement along two Cartesian axes X and Y.

The top section 3 supports a fixed punching head 7, which is conveniently equipped with a tool changing device, and a linear guide 8 for a compass structure 9 which supports a laser cutting head 10 equipped with polar-linear mobility.

The polar-linear mobility of the laser head 10 is ensured by two independent actuators, which in the case of FIGS. 1 and 2 consist of two rotating motors 11 and 12 which move two sliding pads 13 and 14 independently and at a variable reciprocal distance along the linear guide 8. Thereby, the laser head 10 may be moved along the Y axis and may rotate about a vertical axis by means of opening and closing the compass structure (FIGS. 1 and 2).

Alternatively, the actuators 11 and 12 may consist of linear motors (FIG. 3) or of screw motorizations (FIG. 4).

As a further alternative, the linear guide 8 may be arranged perpendicular to base 1 and parallel to manipulator 4, as shown in FIG. 5.

The compass structure 9 is better shown in FIG. 6, where the view comprises two articulated rods 15 and 16 arranged in a V, which have respective ends hinged on the respective sliding pads 13 and 14 by means of pins 17 and 18 with axes perpendicular to the plane of the sheet metal 6 and to one another by means of a further pin 19, it also being perpendicular to the plane of the sheet metal, arranged close to the other end of rod 15, where the laser cutting head 10 is fixed.

The whole formed by the linear guide 8, by the sliding pads 13 and 14, by the actuators 11 and 12 and by the articulated rods 15 and 16 allows low-inertia movements of the laser head 10 along the requested cutting profile, while manipulator 4 determines the movements of the sheet metal in the directions XY with respect to the punching head 7.

As shown in FIG. 7, which refers to the embodiment in FIGS. 1 and 2, manipulator 4 of the sheet metal and the mobility of the laser head 10 are obtained so as never to interfere to each other to allow a through cut 20 from top to bottom of the sheet metal to be obtained by the laser head. 

1. Combined machine for punching and laser cutting of a flat sheet metal, comprising a fixed base (1), a fixed punching head (7), a mobile laser cutting head (10) and a manipulator (4) for movement of the sheet metal (6) in a cartesian plane (XY), characterized in that said laser cutting head (10) is supported by a variable-aperture compass structure (9) which is movable along a linear guide (8).
 2. Machine according to claim 1, characterized in that the double mobility of the laser cutting head (10) is obtained by means of two independent motorizations (11, 12) which cause translation of the compass structure (9) along a linear guide (8) fixed to the base (1) and opening and closure of the same compass structure (9).
 3. Machine according to claim 2, characterized in that said compass structure (9) comprises two sliding pads (13, 14) driven by respective independent actuators (11,12) to move along said fixed guide (8) at variable relative distance and two rods (15,16) arranged at V for articulated connection of said pads (13, 14) to said laser cutting head (10), a first rod (15) having a first end pivoted on a first sliding pad (13) to be rotatable around a first axis (17) perpendicular to the plane of the sheet metal and a second end integrally fixed to said laser head (10) and a second rod (16) having a first end pivoted on a second sliding pad (14) to be rotatable around a second axis (18) perpendicular to the plane of the sheet metal and a second end pivoted with said second end of the first rod (15) to be rotatable around a third axis (19) perpendicular to the plane of the sheet metal.
 4. Machine according to claim 3, characterized in that said actuators (11, 12) are rotary motors.
 5. Machine according to claim 3, characterized in that said actuators (11, 12) are linear motors.
 6. Machine according to claim 3, characterized in that said actuators (11, 12) are of screw type.
 7. Machine according to claim 1, characterized in that the manipulator (4) and the mobility of the laser cutting head (10) are chosen so that they do not interfere with each other in order to allow the complete passing-through cutting of the sheet metal. 